/**
* Mark current page as dirty.
* If there are no deferred writes, the page is immediately flushed to disk.
* If ``force'' is TRUE, we also ignore deferred writes and flush the page.
* @return TRUE on success.
*/
bool
dirtypag(DBM *db, bool force)
{
struct lru_cache *cache = db->cache;
long n;
sdbm_lru_check(cache);
n = (db->pagbuf - cache->arena) / DBM_PBLKSIZ;
g_assert(n >= 0 && n < cache->pages);
g_assert(db->pagbno == cache->numpag[n]);
if (cache->write_deferred && !force) {
if (cache->dirty[n])
cache->whits++; /* Was already dirty -> write cache hit */
else
cache->wmisses++;
cache->dirty[n] = TRUE;
return TRUE;
}
/*
* Flush current page to the kernel. If they are forcing the flush,
* make sure we ask the kernel to synchronize the data as well.
*/
if (flushpag(db, db->pagbuf, db->pagbno)) {
cache->dirty[n] = FALSE;
if G_UNLIKELY(force)
fd_fdatasync(db->pagf);
return TRUE;
}
/**
* Close a stream, flushing data to disk.
*
* This is needed on "ext4" filesystems or any other filesystem which delays
* the allocation of data blocks, in case there is a crash between the close
* and the moment the data is written physically to the disk.
*
* @return the fclose() status.
*/
int
file_sync_fclose(FILE *f)
{
int fd, ret;
g_assert(f != NULL);
ret = fflush(f); /* Send all buffered data to kernel first */
fd = fileno(f);
if (-1 == fd_fdatasync(fd))
s_warning("cannot flush data blocks to disk for fd=%d: %m", fd);
return fclose(f) | ret; /* Report error if fflush() failed */
}
